Thermal comfort greatly impacts a person's productivity and general well-being. Systems that automatically maintain indoor thermal conditions, including heat pumps, refrigeration and/or air-conditioning systems, can provide suboptimal thermal comfort in an energy inefficient manner, often because they are poorly controlled.
For the most part, communication with the thermal conditioning systems take place by either a wall thermostat or a remote control device, whose purpose is to turn the equipment on or off, and set temperature set-points. The on/off switch indicates when service is needed and when it is not. The temperature setting is a way of indicating a desired level of thermal comfort, in accordance with the needs and thermal condition of building occupants. In principle, the conventional thermal conditioning systems should be able to provide thermal comfort, when possible. However, in practice, this may not happen, due to a number of reasons.
For example, occupant(s) of a building rarely know the optimal value of their thermal comfort. That value depends on the current level of physical activity, respectively metabolic rate, the humidity of air, and the clothing worn by the occupant(s). For example, when an office worker has been sitting still at a desk for a long period of time on a cold winter day, the worker is likely to feel cold due to a lower metabolic rate, and request more heating by increasing the temperature set-point. Similarly, when a manual laborer has been performing vigorous physical work on a hot and humid summer day, the worker is likely to feel very hot, and can request more cooling by lowering the temperature set-point. In such a manner, the occupants can overestimate or underestimate their need for thermal comfort, which can lead to dissatisfaction and the inefficient use of thermal conditioning systems.
One way to address this problem is to take the control out of the hands of the occupants of the premises. For example, some methods aim to develop thermal models that are used to automatically sense and control the thermal comfort of the occupants. See, e.g., U.S. 2016/0320081. However, the thermal model creation can be a tedious and uncertain process.
Accordingly, there is still a need to develop new strategies and methods to improve the thermal comfort of building occupant(s), which do not depend on data that are not easily accessible.